found at DigiDirect
The Hoya 72mm HD MkII UV Filter is a general use, clear filter high Density Sharp Cut UV Glass. Aside from the reduction of unwanted blue casts, no additional coloration or contrast is created, and adjustments to exposure are not required while using this filter. To prevent internal ghosting and reflections while providing over 99.35% light transmission, eight layers of anti-reflection coatings are applied to both sides of the glass for a total of 16 layers of coating. These coatings offer a high degree of protection to the filter substrate and helps it to stay clean for longer than uncoated filters. The coating formula associated with HD UV filters also promotes effective cleaning with regard to Water and Oil Repellent, Scratch and Stain Resistant